Probably Your'e right, but you know - last time I was changing front sprocket, unscrewing nut was so hard that I spend hour to do this. This time I was able to do this by hands only, so I realized that this little thing saved me from much damage :/ after that instead waiting for another tab to break, I've just spend $5 for new one.

Probably Your'e right, but you know - last time I was changing front sprocket, unscrewing nut was so hard that I spend hour to do this. This time I was able to do this by hands only, so I realized that this little thing saved me from much damage :/ after that instead waiting for another tab to break, I've just spend $5 for new one.

I've been there too. Those nuts seem to be either super-tight or hand-tight. I suspect due to vibration and usage.